Forum Discussion
For a client with a proven history, I would be more inclined to trust them too. It's a red flag for me when it's the beginning of a relationship. In those cases, I'd rather do a small project first to make sure we're a good fit and earn their trust than go right to price negotiations.
I've asked about volume discounts in other forums (mostly after my last experience to see if it was atypical). I didn't hear from too many other people who are offering it. Several people said they never do discounts; they would negotiate the scope of the project down if budget is a concern. A few people said they might do discounts. 5% seems about right if you're going to do it. There is value in having a reliable client who you don't have to train and where you know the processes.